Re: IP range to CIDR

Alex van den Bogaerdt wrote:
> On Mon, Jan 26, 2004 at 04:01:50PM -0700, Cameron Knowlton wrote:
>> I was wondering if anyone knows of a web page or a Mac OS application =
that can convert from IP
>> ranges to CIDR addresses, e.g.:
>>
>> 200.41.0.0-200.41.127.255 --> a.b.c.d/x
>
> If nothing shows up, and if you can write your own:
>
> Range from "x" upto and including "y", properly aligned.
>
> r=3D(x xor y)
> add one
> shift right until r=3D=3D1, count number of shifts
> subtract from 32.
>
> Example
> 200.41.0.0
> 200.41.127.255
> -------------- xor
> 0.0.127.255
>
> 0.0.127.255
> 1
> ----------- +
> 0.0.128.0
>
> binary:
> 00000000 00000000 10000000 00000000
>
> 15 shift-right,
> 32-15=3D17 --> 200.41.0.0/17
>

Hi Alex!

Take a look at
http://www.isc.org/products/Misc/ or
http://freshmeat.net/projects/aggreg...elease_id=3D9=
1662&topic_id=3D20%2C150%2C857
for "aggregate".

--=20
with kind regards
# make love
make: *** No rule to make target `love'. Stop.